package com.nwpu.coursesupport.tool;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.nwpu.coursesupport.entity.Resource;
import com.nwpu.coursesupport.enumeration.FileType;
import com.nwpu.coursesupport.service.imple.ClassStudentServiceimple;

public class ExcelReader {
	
	private int totalRows = 0;
	private int totalCells = 0;
	private String errorInfo;
	
	protected static Logger logger = LoggerFactory.getLogger(ExcelReader.class);
	
	public ExcelReader() {

	}

	public int getTotalRows() {
		return totalRows;
	}


	public int getTotalCells() {
		return totalCells;
	}

	public String getErrorInfo() {
		return errorInfo;
	}

	public boolean validateExcel(Resource r) {
		/** 检查文件名是否为空或者是否是Excel格式的文件 */
		if (r == null || !(isExcel2003(r.getFileType()) || isExcel2007(r.getFileType()))) {
			errorInfo = "文件名不是excel格式";
			logger.error(errorInfo);
			return false;
		}
		/** 检查文件是否存在 */
		File file = new File(r.getUrl());
		if (file == null || !file.exists()) {
			errorInfo = "文件不存在";
			logger.error(errorInfo);
			return false;
		}
		return true;
	}


	public List<List<String>> read(Resource r) {
		List<List<String>> dataLst = new ArrayList<List<String>>();
		InputStream is = null;
		try {
			/** 验证文件是否合法 */
			if (!validateExcel(r)) {
				System.out.println(errorInfo);
				logger.error(errorInfo);
				return null;
			}
			/** 判断文件的类型，是2003还是2007 */
			boolean isExcel2003 = true;
			if (isExcel2007(r.getFileType())) {
				isExcel2003 = false;
			}
			/** 调用本类提供的根据流读取的方法 */
			File file = new File(r.getUrl());
			is = new FileInputStream(file);
			dataLst = read(is, isExcel2003);
			is.close();
		} catch (Exception ex) {
			errorInfo=ex.getMessage();
			logger.error("抛出异常："+ex.getMessage());
			//ex.printStackTrace();
		} finally {
			if (is != null) {
				try {
					is.close();
				} catch (IOException e) {
					is = null;
					e.printStackTrace();
				}
			}
		}
		/** 返回最后读取的结果 */
		return dataLst;
	}

	public List<List<String>> read(InputStream inputStream, boolean isExcel2003) {
		List<List<String>> dataLst = null;
		try {
			/** 根据版本选择创建Workbook的方式 */
			Workbook wb = null;
			if (isExcel2003) {
				wb = new HSSFWorkbook(inputStream);
			} else {
				wb = new XSSFWorkbook(inputStream);
			}
			dataLst = read(wb);
		} catch (IOException e) {
			errorInfo=e.getMessage();
			logger.error("抛出异常："+e.getMessage());
			//e.printStackTrace();
		}
		return dataLst;
	}

	private List<List<String>> read(Workbook wb) {
		List<List<String>> dataLst = new ArrayList<List<String>>();
		/** 得到第一个shell */
		Sheet sheet = wb.getSheetAt(0);
		/** 得到Excel的行数 */
		this.totalRows = sheet.getPhysicalNumberOfRows();
		/** 得到Excel的列数 */
		if (this.totalRows >= 1 && sheet.getRow(0) != null) {
			this.totalCells = sheet.getRow(0).getPhysicalNumberOfCells();
		}
		/** 循环Excel的行 */

		for (int r = 0; r < this.totalRows; r++) {
			Row row = sheet.getRow(r);
			if (row == null) {
				continue;
			}
			List<String> rowLst = new ArrayList<String>();
			/** 循环Excel的列 */

			for (int c = 0; c < this.getTotalCells(); c++) {
				Cell cell = row.getCell(c);
				String cellValue = "";
				if (null != cell) {
					// 以下是判断数据的类型
					switch (cell.getCellType()) {
					case HSSFCell.CELL_TYPE_NUMERIC: // 数字
						cell.setCellType(Cell.CELL_TYPE_STRING);
						cellValue =  cell.getStringCellValue();
						break;

					case HSSFCell.CELL_TYPE_STRING: // 字符串
						cellValue = cell.getStringCellValue();
						break;

					case HSSFCell.CELL_TYPE_BOOLEAN: // Boolean
						cellValue = cell.getBooleanCellValue() + "";
						break;

					case HSSFCell.CELL_TYPE_FORMULA: // 公式
						cellValue = cell.getCellFormula() + "";
						break;

					case HSSFCell.CELL_TYPE_BLANK: // 空值
						cellValue = "";
						break;

					case HSSFCell.CELL_TYPE_ERROR: // 故障
						cellValue = "非法字符";
						break;

					default:
						cellValue = "未知类型";
						break;
					}
				}
				rowLst.add(cellValue);
			}
			/** 保存第r行的第c列 */
			dataLst.add(rowLst);

		}
		return dataLst;

	}
	
	public boolean isExcel2007(FileType fileType){
		return fileType==FileType.XLSX;
	}
	
	public boolean isExcel2003(FileType fileType){
		return fileType==FileType.XLS;
	}

}
